A novel laser electrodispersion (LE) technique was employed to deposit gold nanoparticles onto Si and SiO(x) surfaces. The LE technique combines laser ablation with cascade fission of liquid metal micro-drops, which results in the formation of nanoparticles upon rapid cooling. The shape and the size distribution of the Au nanoparticles prepared by LE depend on the nature of the support. Gold nanoparticles were also deposited in the channels of microreactors fabricated by wet etching of Si and used as SE(R)RS sensors. The influence of the nanoparticle surface density as well as of the nature of the substrate on the Raman response was studied. At an appropriate surface density of the deposited nanoparticles a significant enhancement of Raman signal was observed showing the possibility to create efficient SERS substrates. Application of microfluidic devices in surface enhanced Raman spectroscopy (SERS) in continuous-flow mode with sensor regeneration is described.

No abstract

No abstract

Articles you may be interested inThermal analysis of diamondlike carbon membrane masks in projection electron-beam lithographyIn projection electron beam lithography ͑EBL͒, most of the e-beam energy is deposited in the resist and substrate as heat. The temperature rise and its effect on critical dimension ͑CD͒ variation and placement error were studied at 100 kV projection EBL for exposure conditions used on a full scale production tool. A few writing strategies were considered. Analytic estimation of temperature rise was followed by numerical simulations using the temperature simulation software tool. Local temperature increases by a maximum of 10.7°C was found at 5 C/cm 2 exposure dose, which corresponds to a few nanometers CD variation and can be over 10 nm depending on the resist and beam blur. Global substrate heating leads to a few tens of nanometers placement error that may suggest a need for better wafer cooling or active placement correction.

No abstract